Improvement in methods of tamping



c. L. KALM BA 'GH. Methods of Tamping. No 155,73l. Patented 0ct .6,18z 4-..

UNITED STATES PATENT OFFICE.

. CHAR-LES L. KALMBAcHjoF n-IcnMoND, VIRGINIA.

IMPROVEMENT IN METHODS OF TAMPING.

Specification forming part of Letters Patent No. 155,731, dated October "6, 1874; application filed June 24, 1874.

To all whom it may concern:

Be it known that I, CHARLES L. KALMBACH, M. E., of Richmond, in the county of Henrico and State of Virginia, have invented a new and useful Mode of Tamping or Stemming Mines Charged with Nitro-Glycerine or kindred explosives; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawing, in which I have shown a mine charged, according to my invention, in vertical section.

The value of tamping a mine before exploding it is'well recognized among all engineers; it economizes explosive material and drilling, increases the efficiency of the blast,

serted at A, andlthen the primer B is lowered 'till it rests well on top of the charge; then a two wads, as shown at 1). Then some ordinary tamping is introduced, which is not very -firmly packed, "as shown at F, leaving a foot or two of the top of the hole for hard ramming, which may safely be driven with bar.

and sledge, the air-cushion preventing all' blowsjrom affecting the charge below. The

IMWA,

and tends to reduce the violent projection of fuse or wires H is or are extended out of the the fragments. Heretofore. such tamping of hole in the, usual manner. v mines charged with nitro-glycerine has been What I claim as my invention, and desire too dangerous to be properly performed, or" to secure by Letters Patent, iseven attempted. The mode of tamping mines charged with My invention consists in providing an airnitro-glycerine, or its compounds, by intercushion between the nitro-glycerine, or simposing an air-cushion in conjunction with ilar explosive, and the tamping material, so as loose and firm"'tamping, substantially as set to avoid the danger of percussive compression forth. v of the charge, while tamping the same, thus In testimony whereof I have signed my ridding that operation of the only and priname to'this specification in the presence of mary cause of premature explosion. two subscribing witnesses.

In the annexed drawing 1 have shown a y CHARLES LFKALMBACH, mine tamped in this manner. Witnesses:

The-hole having been bored to the requisite ASA ROGERS, depth, the charge to be exploded is first in- J. H. HENRY. 

